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As suggested I have just come in from a short run, around 15 miles, on setting 8. I am surprised that it made such a noticeable difference over the 7 setting. It seemed that I needed to open the throttle less for the same pickup and that the bike was keen to accelerate with the smoothness further improved. Cruising in 6th at around 55-60MPH was very comfortable and nipping past traffic didn't need a down change. It maybe my imagination but I seem to have more engine braking and the transition from off to on throttle is seamless. I have no surging anywhere.

When I gave it some beans the machine gathered speed at an almost alarming rate whereas before fitting the XIED it was a bit flat which was particularly noticeable when overtaking.

It will be interesting to see how the fuel consumption is affected but from your posts it looks like it could be more or less neutral depending on my right hand! I just need to get more miles with it which I hope to do in the next couple of weeks.

Thanks Roger, It's available but the cables to connect it arent? And it would require some type of adjustment or setting? Sorry to be "out of the loop" so to speak.

Just to clarify, we have the complete units with R1150 cable instock and ready to ship, here: http://www.beemerboneyard.com/bmwafxied1150.html . Next week we'll have the universal cables that one could use to easily install the unit on an R1100. In about 2-3 weeks we will have a limited # of plug and play R1200 cables. Thanks!
Mike

Yes, that is correct, 2 complete units are needed for the R1200 bikes.
Thanks,
Mike

Just got word that we'll be selling the complete R1200 AF-XiED package for $379.95!! Should have units available hopefully late next week or the week of the 23rd at the latest. When we get them they will be posted here: http://www.beemerboneyard.com/bmwafo2sema.html .
We have just listed an R1100 version (you'll find them at the link above too) that has a universal tap in harness. This is because it may be as long as 6 months before we will have a plug and play harness available for the R1100. It is a simple tie in. Just 2 crimp connections and one tap connection. Eventually we'll have Posi Locks and Posi taps included but for now customers will have to source their own connectors. Soldering is not an option. This was covered in a previous post somewhere and too long of an explanation to put here. We are getting there
Thanks!
Mike

I have had the LC-1 on my 2001 R1150GS for a few months now with good results -- increased torque, improved driveability, and improved mileage in the range of 2-3 mpg.

My 2003 K1200GT (brick engine) has the same Motronic (MA 2.4) as the GS, and with Roger's go ahead I installed one of the new AF-XiED kits on it. I've since ridden about a thousand miles with strikingly good results.

I've ridden the same 400 mile out and back loop twice - about 250 miles of freeway, and 150 miles of twisties. Overall mileage for the freeway portion (up to 75 mph) was 44 mpg, and for the twisties 38 mpg when I rode them hard 43 when I took a more leisurely pace.

This is a striking result for me, since I don't recall getting better than 40 mpg with the K12GT more than once in the 30,000 miles I've ridden it. I can't really say much about increase in torque since the bike is so powerful I never rode it to its limit, but it's still plenty powerful -- lifting the front wheel off the ground under WOT at 6000-7000 rpm in 1st gear. More than I need! I removed the plugs after the first 500 miles with the AF-XiED and they were a nice light tan, indicating the motor was burning cleanly.

Thanks again to Roger for inventing this nifty little gadget that improves the performance of our bikes so much while at the same time improving their efficiency!

The reason a piston engine runs rough is uneven fuel distribution to the cylinders, as you lean you start to starve one cylinder, power goes down in the leaner jug and you get uneven power. The engine shakes or surges due to uneven power pulse. Then as the RPM varies it sets up some standing waves in the induction and exhaust. It is all connected. The fuel system on aircraft is crude. One is a single updraft carb through some pretty crummy plenum and manifolds with different length runners. The other is a very basic mechanical fuel injection system that requires pilot to still set mixture, but most airplane FI systems do use some mechanical mass airflow control of fuel as well as pilots mixture setting. The fuel injectors are just brass injectors that you can "match", but it is a very basic (reliable) fuel system. The design goes back to the 60's. It has not changed. The up draft carbs are similar to ones made for farm tractors, 1940's design has changed little. Again dirt simple and works reliability.

I don't mean to put down enriching the mixture to smooth things out, but you have to admit it is at loses some efficiency, and better spark, better ignition system, better induction would help smooth things out.

I still fly little planes, CFI, ATP. I also build experimental aircraft. I can modify my Lycoming because it is not in a certified airframe. I removed the two magnetos and added dual CDI ignition with variable MAP timing (rpm + manifold pressure sensing). The magneto on aircraft are fixed at 25 degree BTDC (except at start only one mag is used and timing is TDC). After start the second mag comes on line and the other mechanically advances to 25BTC. Also Mags put out a very weak spark, but they are reliable and self powered, isolated from airplanes electrical system. Adding the modern much hotter multi discharge ignition, fuel burn went down and speed increased. Also I can lean much more. Still I have to balance all 4 jugs, otherwise one jug will run rough from over lean condition, while the others are still too rich for max efficiency. I have got my cylinder EGT's pretty even in cruise. It should also be said that aircraft engines are CHT (Cyl Head Temp) critical. They are air-cooled and fuel cooled engines. Also detention could cause engine failure, so at high power, takeoff and initial climb you use full rich mixture and waste fuel, to cool engine and add detonation margin. You can't hear detonation in a plane because it is loud.. You have to be under 75% power to lean. At 10,000 feet a normally aspirated aircraft engine is well under 75%, so you can lean, provided the engine cylinder heads are not too warm. BTW mixture is totally manual on aircraft. The fuel systems, both carb and FI have some compensation as you climb, especially FI. FI on planes uses some very basic manual mass flow (of air) principle.

What about motorcycles? Why does some one not make a CDI ignition system for the BMW, like MSD makes for the car aftermarket?

You and I are in agreement on all these points as to the causes of uneven running. There are some additional thoughts though related to how the owner of one of BMW's big fuel injected twins gets the best they can from their motorcycle. For some reasons, even right up to today, BMW seems to have stayed with their basic mechanical engine design for two cylinder boxer-style motorcycles, and we can't change that we have to work with it.

--To your first point I would add that uneven fuel distribution affects many Oilheads. There is only one O2 sensor so there is no practical way for an R1100 or R1150 owner to balance left right fuel flow which is needed as the engine is leaned. Injector mismatch, closed loop fuel modulation from lean to leaner, and deceleration fuel-leaning during open loop results in AFRs as lean as 16.2:1, I've seen that and measured it, and no amount of tuning can remove it. (For those interested this Gami article does a good job of explaining it: Gami: Causes of Surging .

The R1200 solves the fuel distribution aspect of the uneven running problem by providing separate adaptive control to each cylinder through dual O2 sensorsr. It does an excellent job of equalizing the fuel flow and resulting AFRs in both Open Loop operation (like accelerating) and Closed Loop (like cruising). However, even the R1200 runs meaningfully better with several percent more fuel. I guess that is due to the engine's combustion chamber dynamics.

--To your second point on efficiency losses from running richer, the basic calculations show that if you richen the mixture 6% from 14.7 to 13.8, the engine produces 3% more power. Therefore a 3% loss of efficiency or about 1 mpg. However, up to 60-65 mph on an 1150 you are often running one lower gear (and get to better BSFC, brake specific fuel consumption) because an enriched boxer just happens to run much better from idle to 4500 rpm. If there is a loss of MPG from up to 6% richer, it has been hard to measure.

And is MPG that important to us? If it were wouldn't we be driving a Prius?

--To your third point about CDI ignition, etc. that would not change the AFR imbalance that plagues single O2 boxers.

--One last point that I'll add, there is now an R1100 running with an LC-1. It has been measured in the no-Coding-Plug with adjusted CO Pot configuration. The fueling is about 14.0:1 in the usual operating range, which is 5% richer than the stock catalytic. Why did BMW pick this AFR point when they didn't have to satisfy the EPA? Because it runs better with that extra fuel.

Lee has it right, tune your Boxer well, get it running right, add 4-6% to the fueling, ride for a month. You won't miss dual-spark, and you won't go back to stock fueling. Until you've tried it you won't know what Lee knows.

Just got word that we'll be selling the complete R1200 AF-XiED package for $379.95!! Should have units available hopefully late next week or the week of the 23rd at the latest. When we get them they will be posted here: http://www.beemerboneyard.com/bmwafo2sema.html .
We have just listed an R1100 version (you'll find them at the link above too) that has a universal tap in harness. This is because it may be as long as 6 months before we will have a plug and play harness available for the R1100. It is a simple tie in. Just 2 crimp connections and one tap connection. Eventually we'll have Posi Locks and Posi taps included but for now customers will have to source their own connectors. Soldering is not an option. This was covered in a previous post somewhere and too long of an explanation to put here. We are getting there
Thanks!
Mike

Here is another LC-1 installation as an AFR monitor and another way to richen the mixture, carbs!

first of all thank you to Roger 04rt for sharing his research and data on this and many other threads ... I have experimented using the innovate Motorsports [lc-1] product and found on my bike that running an air fuel ratio of 13.8 gives a big improvement in "driveability". this is really important to me as I am a courier and am on the bike 50/60 hours over 5 days and the lean running drove me insane.

Fuel consumption is vital to me and running 13.8 made little difference overall I think because I changed up the [gear] box quicker in the city negating the maybe 5% loss on the open road. If I had not bought the innovate product, purchasing Roger's [nightrider's AF-xied] is next best thing.

I have found that using RS throtlle bodies helps--sorry no data but perhaps this is because of the different butterfly angle. There is another but more expensive fix using carbs ... this certainly gives you more torque almost across the board for a slight increase in fuel consumption once they are set up correctly. I have been using 40mm R100 Bings for the past 15000 miles/3 months and am very happy with them, not cheap but easy to do. ...

There have been a lot of threads/discussions about Mixture Adaption on the R1100, R1150, R1200 and F800. The range of views about Mixture Adaptation, whether it exists, and its affect on Open Loop fueling, is important when considering fueling improvement products. A quick summary is that Mixture Adaptation is real and that it affects ALL fueling, especially Open Loop.

Because BMW has kept it secret there are many incomplete Motronic/BMSK operating models on the internet, in forums suggesting that Mixture Adaptation is somewhere between: 1) only for Closed Loop, 2) Only at very small throttle angles, 3) only when the throttle is rock steady, or 5) (in one case) a non-existent Urban Legend, I decided to measure the effect of adaptation and show the results. While I was in the middle of the data collection phase, I came across some original Bosch documentation which makes clear the role of Mixture Adaptation in Bosch ECUs.

The bottom line based on the measurements and documents looks like this:
1) Mixture Adaptation is real, it covers all areas of fueling and is necessary for the proper operation of our style of ECUs (Alpha-N, which uses throttle angle as a proxy for air mass/flow). The Alpha-N system is used by the Motronic MA 2.2 and 2.4, as well as all models of the BMSK.

2) The primary Mixture Adaptation Range, as measured in my tests, is +/-20% on the 2004 R1150, which I will show in a coming post. This is a large range and means that any sensor error, sensor modification, ethanol mix change, fuel pressure modification, or intake/exhaust modification can will be learned by the ECU and corrected (Bosch calls these ECUs self-learning). In other words the Open and Closed Loop fueling will revert to BMW's design as long as a stock Lambda (O2, Oxygen) sensor is installed and connected.

3) It appears that Bosch stores a Lambda Correction Factor for every cell covered by Closed Loop and that it creates three Mixture Adaptation values from this matrix of data. Two of the Mixture Adaptations affect short injection times and small TPS angles, and the other Mixture Adaptation affects all areas of the Open Loop fuel map and is intended to correct sensor errors, fuel ethanol content and fuel pressure, to name a few.

4) There are two ways to make permanent changes to fueling: 1) The best is to give the ECU a new reference (LC-1/2 or AF-XIED for BMW) so that the BMSK or Motronic can use Mixture Adaptation to richen fueling automatically, or 2) Disconnect the O2 sensor, with the many perils of that approach--in particular Limp Home mode.

That's the summary. In the next post I'm going to quote Bosch, going all the way back to the early Motronic systems, and then after that post some measurements that clearly show the effect of Mixture Adaptation.

As a preview to the measurements that will be published, in one of the tests Open Loop AFR was enriched to 12.1:1 using a fuel pressure increase and a Booster Plug. In about half an hour of riding Closed Loop at 13.8:1, the Open Loop mixture had adapted from 12.1:1, all the way to 13.7:1. Mixture adaptation made a 15% correction to the Open Loop fueling.

Carbs, Really?

Originally Posted by roger 04 rt

Here is another LC-1 installation as an AFR monitor and another way to richen the mixture, carbs!

Sorry if a dis on carbs offends (pretty much the entire airhead contingent I suspect) and I agree in that carbs are simple and have their place.
If however, eradication of the said fueling and running issues for oilheads is what is being addressed/ considered, then downfitting to Bings seems a far more daunting thankless task than the upgrade to a tunable computer and the required program for superior performance.
I can say that with reasonable confidence having performed such a task successfully, but on an airhead which is far more involved (I can elaborate in case anyone hasn't noted my posts on this subject). Kind of a broken record at this point but sooner or later its going to happen!

Although Bosch introduced the Motronic as an integrated fueling and ignition control computer, what follows are their specific comments on fueling, related to Mixture Adaptation. It should be clear from the following excerpts that Mixture Adaptation is a key, integral part of the Motronic operation. Of particular note for me was that Bosch has been using Mixture Adaptation (or you might call it self-learning) since the mid-1980s, nearly a decade before the first Oilheads.
RB

Excerpts from Bosch Mono-Jetronic - Motronic Documentation 1985-1998The Motronic system is based on indirect measurement of air mass, called an Alpha/n ECU system. Alpha represents the throttle angle and "n" is the engine RPM. This system of indirect measurement of air mass operates with Adaptive Mixture control and super-imposed Lambda Closed Loop control to accurately maintain a constant mixture, without any need for direct measurement of air mass.

The microprocessor is the heart of the Motronic. It is connected by address and data busses to EPROM (which contains program instructions and data tables such as the fuel map) and to RAM which serves to store the Mixture Adaptation values (adaptation: adapting to changing conditions through self-learning).

If the Motronic sees deviations from Lambda=1 in the signals from the oxygen sensor, and as a result is forced to correct the basic injection pulse for an extended duration of time, it generates mixture correction values and stores them in an internal adaptation process. From then on these values are effective for the complete fuel map and are continually updated. This adaptation process ensures consistent compensation for individual tolerances and for permanent changes in the response characteristics of engine and injection components.

The mixture adaptation program is designed to compensate for the effects of production tolerances and wear on engine and injection-system components, including sensors. The mixture adaptation system must compensate for three variables: 1) Influences due to air pressure or temperature, fuel stoichiometry (ethanol content), injector flow rate and system fuel pressure. 2) Influences related to vacuum leakage in the intake tract. 3) Influences due to variation in injector turn-on delay. These three factors are applied to three map areas. Factor #1 is applied (by multiplication) to the entire fuel map. Factor #2 is applied additively in the vicinity of idle. Factor #3 is applied additively in fuel map areas of short injection pulses.

For mixture adaptation, lambda control factors are evaluated using a weighting factor before being added to the adaptation variables.

Limp Home: All sensor signals are continuously monitored for plausibility. If a sensor signal deviates from its defined plausible range, it means that the sensor or its connector is defective. In that case the sensor signal is replaced with a substitute signal that may effect drivability. For example a non plausible air temperature sensor is replaced by the value 20 degrees C. A fault in the lambda sensor results in a shutdown of the complete closed loop adaptive system but will continue to use any past mixture adaptation values if any have been stored. (Editor's note: a shift in the lambda sensor does not cause a fault, but disconnecting the sensor does.)

Next posts: Actual measurements of mixture adaptation on a 2004 R1150.

At the risk of another hand slapping from Henzilla,

Isn't it about time this post was moved to "Opportunities - Members and Vendors
Posts about events, products and services of interest because they have to do with BMW, motorcycles or BMW MOA members."???

I have stuff to sell too and I use "Flea Bay" as it's affectionately called on this forum. I got a gadget I made for oilhead clutches. I didn't think this was the place to make a coin. I might be wrong.

1997 R1100RT (Restored Basket Case) , 1981 KZ 440 LTD (Restored Basket Case)
1986 K75S(the beutch), 1993 K1100RS (blown engine), 1997 Chev Short Box (4x4 with an LT1)
"You can easily judge the character of a man by how he treats those who can do nothing for him."

Isn't it about time this post was moved to "Opportunities - Members and Vendors
Posts about events, products and services of interest because they have to do with BMW, motorcycles or BMW MOA members."???

I have stuff to sell too and I use "Flea Bay" as it's affectionately called on this forum. I got a gadget I made for oilhead clutches. I didn't think this was the place to make a coin. I might be wrong.

Your are wrong.
You may not appreciate the information but I (and if I may speak for the rest of us) DO!
I don't ever read anything positive in your posts, just loud comments or controversial dialog and rough language.
Go back from whence you came, Troll